Can anyone explain how the SR effects such as Time Dilation and Length Contraction are applied at the quantum/Planck scale? Accepting that Planck length and time are the scale at which classical ideas about gravity and space-time cease to be valid, and quantum effects dominate, and are the smallest measurement of length and time that we can theoretically measure with any meaning. Explanations according to and applicable with mainstream physics please will suffice. If tashja is interested in putting his great talent to work, that would also be appreciated. Please Register or Log in to view the hidden image!
My best guess would be that since the Planck scale is a theoretical concept, at which we have never yet observed, and possibly never will, it can never really be shown to invalidate SR. Any other thoughts?
Re Prof. Carlip's statement, (which I couldn't quote for some reason), I have two questions: Is it an issue between discrete and continuous below the Planck scale, and could particles be quantized and quantum gravity be ccontinuous?
just to add here. keep in mind, as humanity advances in knowledge and technology, it will always be measuring smaller and smaller, and measuring larger and larger.
Possibly, we do not know for Q1, and Q2 asking if quantum gravity can be continuous, seems like a contradiction in terms.
Actually, when I came back and reread the thread, I think there is an interesting issue here, and you might have put your finger on it. The OP doesn't directly address the limits of our ability to observe, but what you say is true. As science advances, our ability to observe improves in both the macro and the micro directions. Today's limits on our ability to observe are being advanced rapidly, and it is hard to even keep up with what those limits are, but what ever they are, those limits will give way to the advance of science, and you can be sure that the discoveries will keep coming. In regard to the OP, Paddoboy, were you actually asking if anyone could explain how SR's effects are applied at the quantum level, ... or were you saying that they don't apply, and therefore ... Was it your point that SR could not be falsified even if the laws of quantum mechanics brought it into question someday? First, SR is quite perfect in that the math applies the premise of an invariant speed of light as a common denominator to quantify relative motion in different frames. The effects of the theory, given the mathematics, is that time and distance appear to skew predictably for observers in different frames. The effects of time dilation are observable when identical clocks in relative motion, measure the passing of time, confirming the other premise that the physics are the same in all frames. No one is going to falsify SR by developments at the quantum level unless it can be shown that the speed of light is not invariant, or that the physics are not the same in all frames. Just like science is continually advancing the limits of our ability to observe, science is also advancing our knowledge about the nature of light. Perhaps developments will uncover more details about wave-particle duality, and the nature of the photon at the quantum level. Maybe the understanding of the Planck regime, as limits of nature, may change with those advances. Given the axioms of SR, SR will stand, but given new understandings of light, the axioms will continually be tested.
The Planck scale is the domain of quantum gravity. Relativity theory is a classical theory which makes no predictions for the quantum domain of applicability so neither theory can falsify the theoretical predictions of the other. Relativistic quantum mechanics is a domain of applicability where special relativity and quantum mechanics work together to provide a complete analysis for stuff like high energy particle experiments and other stuff as mentioned in this wiki. http://en.m.wikipedia.org/wiki/Relativistic_quantum_mechanics Happy New Year
